I've measured 3 different Onkyo models and another member measured a 4th and all of them will output >12volts from the LFE jack.

>12 volts into the mini -dsp will clip the crap out of the inputs. There are ways to dial back max volts, but it gets tricky for the not so knowledgeable.

My AVR is putting out a max of 10.6 volts on the sub out chanel. Even dialed way back I'm not able to get the proper headroom in the mini-dsp input side. I would need to dial back max and possibly make other system tweaks or add a line out pot.

>12 volts into the mini -dsp will clip the crap out of the inputs. There are ways to dial back max volts, but it gets tricky for the not so knowledgeable.

My AVR is putting out a max of 10.6 volts on the sub out chanel. Even dialed way back I'm not able to get the proper headroom in the mini-dsp input side. I would need to dial back max and possibly make other system tweaks or add a line out pot.

Clipping the inputs will send a clipped signal down the chain right?

Why does it have to be so f-ing complicated?! Why can't someone just buy some high end components and let-er-rip?

So if it's clipping the inputs then how do you make it not clip? Would a open-DRC be a better choice? It has 8Vrms with the jumper open.

Why does it have to be so f-ing complicated?! Why can't someone just buy some high end components and let-er-rip?

So if it's clipping the inputs then how do you make it not clip? Would a open-DRC be a better choice? It has 8Vrms with the jumper open.

I feel your frustration. If it's clipping the inputs it will clip down the chain, yes.

You make it not clip by not crossing the input limits of the mini-dsp. But once you do that and get say.... 5db of headroom at max listening volume then you have to calculate the boost you apply in the PEQ, and also take into consideration the source material you are feeding it as different material will saturate the inputs sooner than others.

It's not. It just requires some testing, measurement and adjustment. Not everything in the world is plug and play.

All the measurements I need should have already been done by the manufacture....right??

If my Onkyo AVR puts out 12v and the mini's input is 2 max.....how would I adjust that??

I understand there is research to do before a purchase and that's what I'm doing, but why would MiniDSP make a product that can't be used by some AVR's? Or do they work fine, but people are just getting to deep?

One more thing....Is there anyone with a receiver plugged directly into a pro amp who cannot calibrate their sub system to 15dB hot, 90dB with the amplifier trim all the way up and their SW channel trim at maximum? Anyone? I am genuinely curious here. I asked this a couple of times long ago and no one ever replied, which I'm assuming means something.

hahahahaha, late answer here. i have a LT 1300 from ED and i have the volume up on it at 50% /12o'clock position....... BUT on my receiver my subwoofer volume is at 12+ and my right and left surrounds are at 4+. i have an old denon avr-1603 . if i turn the subwoofer level on the receiver down to around 6+ or 7+ i can forget bass!!! i have an 18" AA avalanche in a 540l (approximately) sonotube (tube is 24" diameter and about 64" inches high) tuned to 17hz

If I wanted to how would I measure the SW pre out on my AVR? Volt meter or something?

Yes. Get a test signal source with test tones at 0dBFS, play it through the AVR and use a multimeter to measure the voltage at the sub out on the AVR, output of the MD and the power amp output (speaker terminals). The latter you do by getting the 8R power, say 400W, multiply by 8 and square root the result. This gives you the RMS voltage 56.56Vrms which is the maximum for your amp.

Yes. Get a test signal source with test tones at 0dBFS, play it through the AVR and use a multimeter to measure the voltage at the sub out on the AVR, output of the MD and the power amp output (speaker terminals). The latter you do by getting the 8R power, say 400W, multiply by 8 and square root the result. This gives you the RMS voltage 56.56Vrms which is the maximum for your amp.

Test tones from REW work?

I understand what 0dbFS is....(reference right) what does FS stand for?

I tried using my sub with just a mini dsp without a cleanbox and I was not impressed. Sealed subs without a signal booster just sound anemic to me.

I don't think it has anything to do with sealed versus ported. If your amp requires a cleanbox to boost the signal, chances are that a ported sub with your signal chain would also have the same problem.

I don't think it has anything to do with sealed versus ported. If your amp requires a cleanbox to boost the signal, chances are that a ported sub with your signal chain would also have the same problem.

+1. Consumer level is -10dB, pro level is +4dB, and that's the issue, not the cab design. OTOH a sealed sub can sound anemic irrespective of the signal chain if the room is too large to provide adequate cabin gain.

hahahahaha, late answer here. i have a LT 1300 from ED and i have the volume up on it at 50% /12o'clock position....... BUT on my receiver my subwoofer volume is at 12+ and my right and left surrounds are at 4+. i have an old denon avr-1603 . if i turn the subwoofer level on the receiver down to around 6+ or 7+ i can forget bass!!! i have an 18" AA avalanche in a 540l (approximately) sonotube (tube is 24" diameter and about 64" inches high) tuned to 17hz

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You said... "i have a LT 1300 from ED and i have the volume up on it at 50% /12o'clock position"... Exactly my point...

No offense, but not one of the people who have answered that post have done so correctly. It REQUIRES measurements or simple objective tests. The ears will not be involved. There was no mention of calibration measurements at all. No one has shown their equipment unable to calibrate the SW channel to the same level as the mains or even 12dB hot yet. It requires simple measurement of the output using nothing more than a cheap SPL meter and the built in pink noise of the receiver. Claims of the receiver not having enough pre out voltage to get full power from the "pro" amp also require a few very simple tests to verify concretely one way or the other but few people do them. Those that do never seem to end up using a "bump" box because they find it is not required.

I don't think it has anything to do with sealed versus ported. If your amp requires a cleanbox to boost the signal, chances are that a ported sub with your signal chain would also have the same problem.

I agree. What I meant is sealed subs are inefficient in comparison to 98db sensitive, ported speakers. So I always feel like Ive had to crank my sealed subs more while running the sub trim at +10db to get what I consider satisfactory bass without a bump box.

Yes. Get a test signal source with test tones at 0dBFS, play it through the AVR and use a multimeter to measure the voltage at the sub out on the AVR, output of the MD and the power amp output (speaker terminals). The latter you do by getting the 8R power, say 400W, multiply by 8 and square root the result. This gives you the RMS voltage 56.56Vrms which is the maximum for your amp.

This^^^

With the proper reference source and the AVR MVL = '0' and the SW output @ '0', there's no way anyone measured 12V from any Onkyo receiver.

Once you've balanced the output of SW jack with the input sensitivity of the Mini, you then have to face the reality of the power supply being used with the Mini. Boost can easily clip PS rails depending on the PS circuit being used and the amount of boost needed (preferred).

Once that's settled and the output of the Mini is not clipping the input of your amplifier, the amps gains must be set for the incoming signal and the speakers being driven by the amp.

I use actual scenes from movies for a worse-case signal out of the signal shaper (Mini, DCX, or whatever), after the AVR SW jack. The hottest scenes were from HTTYD, WOTW. With the Onk AVR set to MVL = '0' and the SW trim also at '0' and my analog SEQSS set to +10dB Boost, the highest reading was just under 10V. I then set the gain range for the amplifier (an all-new, modded 14K "clone"), used the AVR SW trim to calibrate SW level (which required lowering the SW trim to -3dB) and I use the amps gain attenuator knob to run the subs hot if and when...